These lipids are classified physically based on their appearance. These are either solid or liquid lipids at normal temperature and they are also known as visible fats. The common solid visible lipids are found in margarine, lard and salad dressings while liquid visible fats are found in cooking oils.
These types of lipids are also called invisible fats because they occur in transparent form of compounds found in egg yolks, milks, olives, avocados and marbled meats.
These are lipids that become saturated fatty acids after digestion and contribute to the formation of "bad cholesterols" (low density lipoproteins). These are commonly found in butter, animal fats, coconut oil and palm oil. The structure of saturated fatty acids on lipids is shown in image 1.
There are lipids that form polyunsaturated fatty acids such as omega 6 and omega 3. These lipids contribute to the formation of "good cholesterols" (high density lipoproteins) in our body and can be obtained from vegetable oils, corn oil, sunflower oil, canola oil, salmon, anchovies, sardines, mackerel and herring. The structure of unsaturated fatty acids on lipids is shown in image 2.
Biological lipids are storage and membrane components of body organs.
There are eight major types of biological lipids: fatty acids, glycerolipids, glycerophospholipids, sphingolipids, sterol lipids, prenol lipids, saccharolipids and polyketides. They are naturally synthesized by the cells found in our membrane tissues, brain, bile, nerve tissues, liver and spleen.